Material handling industrial truck



Dec. 18, 1951 F. c. HEIDRICK ET AL MATERIAL HANDLING INDUSTRIAL TRUCK 5Sheets-Sheet 1 Filed Dec. 6, 1948 INVENTORS .F'. CJiez'dz-ick yJflJCeio'rick 'Dec. 18, 1951 F. c. HEIDRICK ET AL MATERIAL HANDLINGINDUSTRIAL TRUCK 5 Sheets-Sheet 2 Filed Dec. 6, 1948 INVENTORS' FCJ'CBidriCk By Jfi. eidricb nrrrs Dec. 18, 1951 F. C. HEIDRICK ET ALMATERIAL HANDLING INDUSTRIAL TRUCK 5 Sheets-Sheet 5 Filed Dec. 6, 1948INVENTORS F. Oiieidricb BY flJ-eidz'zcb 1951 F. c. HEIDRICK' ETAL2,578,802

MATERIAL HANDLING INDUSTRIAL TRUCK Filed Dec. 6, 1948 5 Sheets-Sheet 4INVENTORS Dec. 18, 1951 F. c. HEIDRICK ETAL 2,578,802

MATERIAL HANDLING INDUSTRIAL TRUCK Filed Dec. 6, 1948 5 Sheets-Sheet sFig. 5

IN VEN TORS f7 Cifieiaricb BY J. flJ-ieidricb Mimi;

Patented Dec. 18, 1951 UNITED STATES PATENT OFFICE.

Fred C. Held-rick and Joseph A. Heidrick, Woodland, Calif.

ApplicationDecember 6, 1948, Serial-No.-6$,*66'6 -,Claims. 1.

This invention is directed to; and it is anobject to provide, animproved fork-lift type of load handling machine; the machinebeingespecially designed, but not limited,- for use to pick up stacks ofbaled hay and load su'chstacks on a transport truck, or to remove thestacks from a truck and pile the stacks onthe ground.

Another object of the invention is to provide a material handlingmachine; as above; which includes a novel, forwardly projecting for-kassembly; each fork being inthe for-m of a screw or auger, and saidscrews being simultaneously and reversibly driven to assist intheloading or unloading of the machine.

A further object of the invention isto provide a material handlingmachine, ofthe type described, which includes a novel,- clam'pingorholddown frame adapted to forcefully engage a supported load from abovewhereby to prevent accidental displacement of said load from the forkassembly upon movement of the machine from the pick-up point to thedischarge point; such frame being mounted and power actuated in a uniquemanner.

An-additional object ofthe invention is to .provide a material handlingmachine, as in the preceding paragraphs, wherein both the screw forkassembly and the load clamping or hold-down frame are mounted on avertical movable elevator frame, and both power actuated by mechsignedfor ease and economy of manufacture, and

the machine being a rugged and reliable structure.

A further object of the invention is to provide a practical materialhandinggmachine; and one which will be exceedingly effective for thepurpose for which it is designed These objects are accomplished by meansof such structure and relative arrangement of parts as will fully appearby a perusal of the following specification and claims.

In the drawings:

Fig. l is a side elevation ofthe machine showing a stack of baled hay asinitially picked. up from the ground. I

Fig. 2 is a similar view, but shows the stack of baled hay clamped onthe fork assembly, and the machine maneuvered to position the stack ofbaled hay above a truck bed for unloading.

Fig, 3 is likewise a similar view, but; shows the position of the partsas the stack of baled hay is unloaded onto the bed of the truck.

Fig. 4 is a sectional plan view showing the screw fork assembly.

Fig. 5 is a fragmentary end elevation showing the drive for the screwfork assembly.

Fig. 6 is a plan view, particularly of the clamping or hold-down frame.

Fig. 7 is an end view of said clamping or holddown frame.

Referring now more particularly to the characters of reference on thedrawings, the machine comprises a wheeled, self-propelled vehicle,indicated generally and in part at I such vehicle including alongitudinal main frame 2- supported, at the front, by transverselyspaced, pneumatic tire wheels 3, and supported,at the rear, by simiiarbut driven wheels (not shown) At its front end the frame 2 is fitted",between the wheels 3, with an upstanding guide-frame 4 which is mountedfor rearward tilting motion; such rearward tilting motion beingaccomplished by linkage, indicated generally at 5, operated by a fluidpressure actuated power cylinder 6. This arrangement is generallyconventional in fork lift type trucks.

In front of the upstanding, guide framed there is a verticallyelongated, rectangular elevator frame I mounted in connection with theguide frame 4 by means of a carriage, shown in part at 8. This carriageB is power raised or lowered in the guide frame 4 by suitable mechanism(not shown), which may be of a typeconventional to fork lift typetrucks, and which mechanism is under the control of the operator fromhis station on the truck.

At its lower end the elevator frame 1- is provided with a forwardlyprojecting fork assembly, indicated generally at 9, and adapted for theengagement beneath a load in supporting relation thereto; such forkassembly comprising the following structural arrangement:

The lower end ofthe elevatorframe I includes a rigid bottom cross beaml0, and a plurality of elongated screw forks H project forwardly fromsaid cross beam in equally spaced, parallel relation. The screw forks Hare journaled, at their rear ends, in connectionwiththe cross beam inand project therethrough; there being sprockets 12 on the rear ends ofthe screw forks H for driving the same. An endlesschain l3 drives thesprockets H in the manner illustrated in Fig. 5; the driving run of saidchain cooperating with said sprockets H2 in under and over relationship,as shown. This means that certain ofthe screw forks I I turn opposite totheothers, and the lead or pitch of said screws is set so thatwhenrotated by the drive, which is reversible, said forks all move theload in an unloading, or loading direction.

The endless chain I 3, and consequently the sprockets I2, is reverselydriven by a motor l4 mounted in the elevator frame I, which motorincludes a drive sprocket l5 over which the chain I3 is trained. Themotor I4 may be of any suitable type, but is here shown as a pressurefluid driven motor interposed in a. pressure system including conduits,indicated in part at It, which system is controlled by the operator fromhis station on the machine.

At their outer ends the screw forks H are tapered, as at H, tofacilitate their insertion beneath a load.

At its upper end the elevator frame 1 supports a forwardly projecting,vertically swingable, load clamping or hold-down frame unit, indicatedgenerally at 3, which is constructed as follows:

On opposite sides, and at the top, the elevator frame 1 includes rigidrearwardly projecting brackets l9, and side arms 20 are pivoted, attheir rear ends, as at 2|, to corresponding brackets |9, and thenceproject forwardly to a termination generally above the fork assembly 9intermediate its ends.

The side arms 20 are adapted to be simultaneously power raised orlowered bymeans of a double acting power cylinder 22, pivotallyconnected to each in upstanding relation between the corresponding sideof the elevator frame I, as at 23, and a point on the corresponding sidearm 20 ahead of its pivot 2|, as at 24. The power cylinders 22 aresimultaneously actuated by a fluid pressure system including conduits 25which lead to each cylinder 22; said system being valve-controlled bythe operator from his station on the vehicle. The side arms 29 span onopposite sides of a rectangular frame 26, and said side arms pivotallyconnect at their forward ends, as at 27, to opposite sides of the frame23 centrally of its ends, whereby said frame 23 is rockable relative tothe side arms 2|]. Normally, however, the frame 26 is maintainedparallel to the side arms 20 by opposed spring, counterbalancing units28 mounted on the side arms 20 and including rods 29 coupled to cars 33which upstand from opposite sides of the frame 26.

The frame 26 includes a plurality of cross bars 3|, and each thereof isfitted with a plurality of spaced, dependent spikes 32 adapted for loadengagement.

In operation of the above described machine the clamping or hold-downframe i8 is initially set by the power cylinders 22 at a forward andupward incline, and to pick up a load, such as a stack of baled hay 33,the vehicle I is manipulated in a direction to cause the screw forkassembly 9 to project beneath such stack. At this time the screw forksII are run in a direction to aid in the loading of the stack onto saidfork assembly. In other words, the screws act to pull the load towardthe elevator frame 1. At this point it should be noted that as certainof the forks II have a lead or pitch opposite to the others and turn inopposite directions, side draft on the stack is minimized.

After the stack of baled hay 33 is loaded onto the fork assembly 9, inthe manner shown in Fig. l, the power cylinders 22 are actuated so as topull downwardly on the side arms 20, swinging the clamping or hold-downframe unit I 8 into engagement with the top of said stack of baled hay33. At this time the frame 26 lies flush or horizontal on top of thestack 33, with the spikes 32 penetrating the uppermost bales 34 of saidstack in the manner shown in Fig. 2. This effectively clamps the stack33 between the frame unit [8 and the screw fork assembly 9, whereby saidstack may be carried on the vehicle from the pick-up point to thedischarge or unloading point without tendency of the stack to tip orspill. Also, if desired, the upstanding guide frame may be tiltedrearwardly so as to correspondingly tilt the elevator frame 1 wherebythe stack 33 tends to hold rearwardly against said frame 1.

After the stack of baled hay 33 is loaded on the fork assembly 9, andclamped from above by the clamping or hold-down. frame unit |8, as abovedescribed, the elevator frame I is run upwardly until the fork assembly9 is in a horizontal plane higher than the bed 35 onto which the stackis to be deposited. Then. the vehicle I is manipulated until the stack33 is directly over the bed 35 of the truck 36; the elevator frame 1then being lowered until the bottom of the stack rests on a plurality oftransverse cross members or stringers 3'! on said truck bed 35.Thereafter, the clamping or hold-down frame unit I8 is raised toreleased position, and the vehicle I moved slowly away from the truck 36(see Fig. 3), with the screw forks of the fork assembly 9 running in adirection tending to unload the stack 33; said screw forks turningbetween the stringers 3'|. In this manner the stack 33 can be readilyand easily discharged from the fork assembly 9 onto the truck bed 35.

It will be recognized that stacks of baled hay can be unloaded fromtrucks and placed on the ground merely by a reversal of the abovedescribed truck loading steps.

The described invention provides a very practical and effective machinefor the handling of stacked loads, particularly baled hay; the handlingbeing accomplished rapidly and without the necessity of individuallymoving the bales, and further avoids the necessity of the use of palletsfor each stack.

The structure is rugged and works smoothly, even when handlingrelatively large stacks of substantial weight.

From the foregoing description it will be readily seen that there hasbeen produced such a device as substantially fulfills the objects of theinvention, as set forth herein.

While this specification sets forth in detail the present and preferredconstruction of the device, still in practice such deviations from suchdetail may be resorted to as do not form a departure from the spirit ofthe invention, as defined by the appended claims.

Having thus described the invention, the following is claimed as new anduseful, and upon which Letters Patent are desired:

1. A material handling machine comprising a vehicle mounted, verticallyadjustable elevator frame, a rigid cross beam at the lower end of theelevator frame, a plurality of screws journaled in connection with thebeam and projecting forwardly as a fork assembly, and power means tosimultaneously rotate said screws; said power means including a motor onthe elevator frame, and an endless drive connected between the screwsand motor.

2. A material handling machine comprising a vehicle mounted, verticallyadjustable elevator frame, a fork assembly projecting forward from thelower end of the elevator frame, and a vertically adjustable loadhold-down unit projecting forward from the elevator frame in spacedrelation above the fork assembly; said load hold-down unit comprising apair of transversely spaced arms pivoted to and projecting from theelevator frame, power means to simultaneously swing said arms up ordown, a load engaging frame disposed between the arms, and meanspivoting said load engaging frame intermediate its ends to the armsadjacent their free ends for vertical rocking motion of said frame.

3. A material handling machine comprising a vehicle mounted, verticallyadjustable elevator frame, a fork assembly projecting forward from thelower end of the elevator frame, and a verticall adjustable loadhold-down unit projecting forward from the elevator frame in spacedrelation above the fork assembly; said load hold-down unit comprising apair of transversely spaced arms pivoted to and projecting from theelevator frame, power means to simultaneously swin said arms up or down,a load engaging frame disposed between the arms, and means pivoting saidload engagin frame intermediate the ends to the arms adjacent their freeends for vertical rocking motion of said frame, there being yieldablemeans between said load engaging frame and arms tending to maintain theframe in predetermined position relative to the arms.

4. A material handling machine, as in claim 2, including cross membersin the load engaging frame, and spikes depending from said crossmembers.

5. A material handling machine comprising a vehicle mounted, verticallyadjustable elevator frame, a fork assembly projecting forward from thelower end of the elevator frame, and a vertically adjustable loadhold-down unit comprisin a pair of transversely spaced arms pivoted toand projecting from the elevator frame, a fluid pressure actuated powercylinder assembly connected between the elevator frame and arms tosimultaneously swing the latter up or down, a loading engaging framedisposed between the arms, and means pivoting said load engaging frameintermediate its ends to the arms adjacent their free ends for verticalrocking motion of said frame.

FRED C. HEIDRICK.

JOSEPH A. HEIDRICK.

REFERENCES CITED Thefollowing references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 214,929 Lockeet al Apr. 29, 18791,300,620 Joy Apr. 15, 1919 1,564,926 Armstrong et al. Dec. 8, 19251,896,543 Gfrorer Feb. 7, 1933 1,900,569 Lederer Mar. 7, 1933 1,971,952Townsend Aug. 28, 1934 2,281,012 Sears Apr. 28, 1942 2,403,356 FrancisJuly 2, 1946 2,420,828 King May 20, 1947 2,432,182 Turner Dec. 9, 1947

